Designs have been proposed for container closures which include a latch for holding the closure closed and preventing the opening of the closure unless the closure latch is manipulated in a specific manner. Some such designs are particularly suitable for use as child-resistant closures.
The U.S. Pat. No. 5,356,017 discloses a closure having a child-resistant latch. The closure has a base or body adapted to be mounted on the container over the opening and defines a discharge aperture through which the container contents can be dispensed. The latch includes a locking member in the form of a lever projecting upwardly from the closure body.
A lid is hingedly connected to the body for movement between a closed position occluding the discharge aperture in an open position spaced from the discharge aperture. The lid defines an aperture for receiving the lever when the lid is closed so that the lever engages an adjacent portion of the lid and holds the lid closed.
In order to open the closure, the lever must be pushed in one direction while the lid is lifted. This requires the use of some fingers of both hands, as well as some significant finger strength. Small children are not capable of performing the necessary manipulations with strength sufficient to open the closure.
While the above-discussed child-resistant closure functions well, it would be desirable to provide, in some applications, a tamper-evident feature on the closure. Preferably, such a tamper-evident feature should prevent operation of the latch unless the tamper-evident feature is removed. Further, the removal should result in a readily observable, altered configuration or appearance which will be immediately indicative of the removal of the tamper-evident feature or portion thereof.
It would also be desirable to provide an improved tamper-evident feature suitable for use with a variety of latched closure designs which could be relatively easily incorporated in such existing closure designs.
Further, it would be beneficial if such an improved tamper-evident design could be readily employed with various types of child-resistant closures as well as non-child-resistant closures.
It would also be advantageous if such an improved tamper-evident design could be readily fabricated from thermoplastic materials and include separate pieces of contrasting color.
It would also be beneficial if such an improved closure could be provided in a form that would not require excessively complicated manufacturing operations and that would permit the use of conventional, high-speed, automatic capping machines for applying the closure to a container.
The present invention can be embodied in designs that provide one or more of the above-discussed benefits and features.